Despite the dates of the movie releases, here is the timeline of the Marvel Cinematic Universe, according to marvelcinematicuniverse.wikia.com.
Before the Universe began, six singularities existed. These were formed into the six Infinity Stones (Space, Mind, Reality, Power, Soul, and Time) by the Cosmic Entities sometime after the Universe came into existence. The Celestials use the Power Stone to impose judgment upon enemy civilizations. Over time, the Beings are overwhelmed by the Stone's power and attempt to dispose of it by encasing it in an Orb and storing it away in the Temple Vaulton Morag.
Thousands of years ago, in order to raise their chances in the war against their enemies, a rogue Kree faction visits numerous planets, genetically altering a number of sentient life forms in order to create biological weapons. One of the planets visited is Earth, and the Kree's experiments give rise to a unique caste of genetically altered Humans. When these humans are deemed ready for war, the Kree expose them to Terrigen Mist, which activates their special genetic ability of Terrigenesis; a process which imbues the human with a power unique to them. They construct the Diviners, containment devices built to hold Terrigen Crystals. The Diviners will only open if one of these genetically altered humans brings them to a cityscape built beneath the planet's surface, releasing the mist so as to "divine" those who have the altered Terrigen Gene. The Kree hierarchy discovers the faction's illegal activities and the operation is abandoned. The Kree disperse from Earth, leaving behind six Diviners, the city, and at least one of their deceased kin. These genetically altered humans eventually start to call themselves 'Inhumans.'
|400BC||A powerful Inhuman, referred as Alveus, is created by the Kree to dominate the rest of his race, but eventually ovepowered his own creators and banished them from Earth. The humans and Inhumans banished him to a distant planet. Maveth, through a Kree Monolith. Followers of the exiled Inhuman founded a secret society (HYDRA) and start planning its return to Earth in order to let him rule it.|
|1014||The Kree and Nova Empires engage in a war which lasts a thousand years.|
|1409||Odin hides the Tesseract in Tønsberg, Norway.|
|1942||In Tønsberg, Norway, Johann Schmidt discovers and takes the Tesseract, hidden within a monastery. He refers to it as "the jewel" of Odin's Treasure Room.|
|1943||Frustrated by his lack of real action, and learning that Bucky Barnes is trapped behind enemy lines, Steve Rogers attacks a HYDRA facility in Austria and releases Dum Dum Dugan, Gabe Jones, Jim Morita, James Montgomery Falsworth, Jacques Dernier, Bucky, and the rest of the 107th. Johann Schmidt sets the facility to self-destruct and escapes with the Tesseract. During his escape Rogers memorizes a map of HYDRA facility locations and obtained a sample of the power source HYDRA was using.|
|1944||Howard Stark examines a sample of HYDRA's power, which will help him develop a framework to synthesize a new element. Also, the Howling Commandos board a HYDRA train and capture Arnim Zola. In the ensuing battle with HYDRA agents, Bucky Barnes falls from the train and is presumed dead.|
|1945||Steve Rogers battles Red Skull. As the Red Skull escapes in the Valkyrie, Captain Americagains access to the plane and a fight ensues. Red Skull handles the Tesseract, which activates and sends him through a portal. The Captain crashes the Valkyrie off the coast of Greenland so its bombs never reach the USA.|
|1988||Peter Quill is taken from Earth.|
|2005||Bruce Banner radiates himself to become the Hulk.|
|2008||Phil Coulson and Melinda May are dispatched to Bahrain to kill an inhuman. May receives the nickname, the Cavalry. She resigns field work.|
|2009||Phil Coulson in charge of Project TAHITI.|
|2010||Tony Stark captured, and Ironman created. The Avengers Initiative is revealed to Stark.|
|2011||Stark Industries World Expo. Thorns Hammer is discovered in New Mexico. Thor appears on earth. Hulk appears at Culver University. SHIELD is funded to research the Tesseract.|
|2012||Steve Rogers is discovered alive in the ice. Loki and Thanos make an agreement about the Tesseract, which leads to the Battle of New York, where the Avengers defeat of the Chitauri Invasion. Phil Coulson dies. The Iron Legion is created.|
|2013||Project Deathlok begins. Grant Ward is promoted to Level 7 in SHIELD. Battle of Vanaheim occurs in Asgard. The Battle of Greenwich occurs on Earth. The Asgardians are keeping two infinity stones, but visit with The Collector about possibly moving one. The Collector hires Gamora to retrieve another infinity stone.|
|2014||Coulson discovers the meaning of TAHITI and that GH325 owes its origin to the Kree. HYDRA subverts SHIELD. The Winter Soldier is discovered. Nick Fury goes into hiding. Grant Ward betrays Phil Coulson. Across the galaxy, Peter Quill discovers the infinity stone Gamora has been hired to retrieve. Quill forms the Guardians of the Galaxy to defeat Ronin, the fundamentalist Kree. Quill learns there is something ancient in his own DNA and that his father is something unknown. The infinity stone is given to the Nova Empire.|
|2015||SHIELD rebuilds and starts to stabilize. Ultron becomes self-aware and attempts to create a form, but instead creates The Vision, who might be in possession of an infinity stone. Ultron tries to destroy humanity. The Hulk goes insane. Inhumans begin to spontaneously go through Terrigenesis.|